It is very hard to find collagen as the main ingredient in a serum, so Neocell is the best out there.
Twinlab used to make a better product-a collagen elastin gel that really was great but it was discontinued many years ago. I'll have to settle for this serum which does tighten up the skin upon application. I suspect that a lot of the serum will be lost within the pump however. Doesn't take much though to apply to face, maybe a scant 1/2 tsp.

just use a few time since deliverer, i can't say i like it - it drys quick once apply, but don't feel any improvement in skin, just feel dry, and the next morning looks dry as well. i normally buying the vitamin c serum here in iherb for many years, thought to change the brand since getting older may require more collagen supply, but so far, don't feel any good sign with this, may continue use till finish if not find anything else better.

This is a pretty good serum. Pleasant scent, and helps with small wrinkles. Could be a little bit cheaper (or have more serum for the same price). Nice looking product. Also good that this is paraben free.

Absorb into the skin fast, like a water feel. Not moist enough for only one skin care at night. Needed to apply some moisturizer. But for oily skin in the humid hot weather, this is the answer for daily use.